Line drawing attachment for typewriters



Aug. 3, 1948.

L. CLARK LINE DRAWING ATTACHMENT FOR TYPEWRITERS Filed July 2, 1946 Bradley L. Clark m/ Awm l aiente d Aug. 3, 1948 UNITED STATES OFFICE LINE DRAWING ATrAeaMENT m. TYPEWRI'EEBS Bradleyli. Clark, RiockvilIe', Md'-.

ApplicationaJ-uly 2., 1946,: Serial No, 6813022,

2' Claims; 1.

This invention relates to a. typewriter attachment for producing a line on the paper,. either solid or dotted, and either verticalor transverse, through continuous pressure ofoneof thecharacter keys, correlated with the operationof-means, such as the tabulator key, for making the platen slide, or the spacing lever or knob for causingithe platen to rotate.

One of the objects of the invention istoprovide as anattachment, a line drawer readily slipped over the type end of any convenient, type bar and instantly removed when desired.

Another object of the inventionristo-providea line drawing device adapted to, be detachably; carried solely by the type block at theend oft any selected type bar, overlying the type. characficrr on the face of said type b1o c k,- and substituting? therefor ribbon engaging, stylus means formin -a part of said device Still another object of'theinventioniis thezmfle vision of a device of'the class described-having stylus means in upper and lower caserposltions, so located as to underline the text in ,eithenupperor lower case.

Another object of the invention is the provision of a line drawing attachment having resilient clamping means for supportingit on the, type block.

Another object of the invention is to provide a line drawing attachment for-typewriters, which is simple in construction, inexpensive tomanurfacture, which can be purchased as a gadget to-be appliedto any characterkey of any. typewriter when needed, without the use of tools, and removed with equal facility when not needed.

Other objects of the invention will appear as the following description ofapreferred andpractical embodiment thereof proceeds;

In the drawings which accompany and form a part of the following specification, and throughout the figures of which the same reference characters have been used to denote identical parts:

Figure 1 is a perspective view, partly in section, of a line drawing device embodying the principles of the invention;

Figure 2 is a side sectional view showing the line drawing device applied to the type block at the end of a type bar;

Figure 3 is a front view of the device;

Figure 4 is a side View of a conventional train of linkage between a character key and type bar, showing the line drawing device of the subject invention intercalated between the type block and platen.

Referring now in detail to the several figures,

J 2i the numeral, I represents .the line drawing attach: ment as a whole. This comprises a base. plate 2, having opposite resilient side Wings 3, a top strap i bent} perpendicularlyto the baseplate', above the side wings,anctaresilient tongue 5 bent down fromthe rear of the top strap and preferably having: a re-entrant bend 5 near its free end.

The base: plate, side wings, top strap and tongue, together form a, socket which is sized to fitover the type; block at the end of the type bar of. a conventional typewriter, clampably engaging the same, the. base-plate over-lyingv the type block, the sideawings pressing the sides of said block, and thetonguepressing the; back of the block. and drawing. thebaseplateinto firm-contact withthe type. The top strap rests upon the: top of the type-block =and"- thus definitely positions the ime drawing-. device. 7 Since all of thetype blocks of asingle typewriter are; identica;las to size and shape, the line drawing device may be selectively slippedupon any; desired type block-.- Usually the type block of a littleused-characten-will beselected. Due to the::fact ,that the device; is: held: in; place solely through-the resilience of the socketconstruction, it;issobvious -qthat it can; be slipped on oroff: in a moment; requiring? no-;too.ls.-

Sinceits isximp ortant that the type blo ck shallnot be scratched; particularly the typeface, it isri preferred tiorline: the socketlwithz alm teri softer: than; that of the type: block;v Figure 1 showsthe: inneri walls; of the socket coated with !a film lg-.ofisoft-plastlc, toprevent scratching, A

for: the stylusaelementsx H and:, I2; which press;

the ribbon, the element I I being a ball for making a solid line, the element I2 being a toothed wheel for making a dotted line. Each box has a flat front face, respectively I3 and Id. The front face I3 has a hole slightly less in diameter than the ball I I. The ball is inserted from within the box, projecting through the hole, and is retained by a pin I5, at its rear, fixed at its opposite ends in the walls of the box. The front face i l of the box I0 has a slot through which projects a portion of the wheel I2. The latter is journaled on a pin I6, fixed at the opposite walls of the box 10. The box is converged toward said front faces, thus avoiding contact with the ribbon by the edges H, which might cause a spurious imprint.

Referring to Figure 4, this shows any character key I8 of a typewriter, in depressed position, the

depressed. I

Since in the present invention the production of the line is dependent upon sustained pressure upon the character key while the platen moves,

it is obvious that the invention must provide for: taking up this lost motion. This is done by making the depth dimension of the boxes 9 and Ill such that the distance from the inner face of platen when the corresponding character key is in depressed position.

While I have in the above description disclosed a preferred and practical embodiment of the invention, it will be understood by those skilled in the art that the details of construction and arrangement of parts are capable of variation without departing from the invention.

jWhat I claim as my invention is:

1. Line drawing attachment for typewriters adapted to be spring retained on the type end of any type bar of a typewriter comprising means forming a resilient socket including a base plate having integral opposite convergent resilient side wings extending substantially to the lower end thereof, a top strap extending above said side wings f-roni the upper end of said base plate integral, therewith and perpendicular thereto, a

the base plate to the foremost point of either the ball or toothed wheel is at least as great as the range of free movement between the type block and" platen.

It is preferred to place the boxes 9 and ID in such position on the base'plate that the bearing points of the stylus elements shall underline words or passages of the typed'text. Figure 2 shows the upper and lower case characters 28 and 21, the bearing point of the ball ll being below the level of the bottom of the character 28 and the bearing point of the wheel 12 being below the bottom of character 21.

To make a horizontal line, the attachment having first been mounted upon any desired type block, it is necessary merely to depress the corresponding character key, thereby pressing the stylus element against the ribbon, then to-release the carriage by pressing the tabulator key-or to slide the carriage by hand. Sliding of the paper against the pressure point of the ribbon produces the mark which is continuous so long as the character key is held depressed.

To make a vertical line, the character key is depressed as before, the platen with the paper being rotated by manipulating the spacing lever or the spacing knob (not shown), at the end of the platen, while the character key is being held depressed. The stylus elements H and [2 roll upon the ribbon as the latter is fed, avoiding undue wear or tearing of the ribbon.

The number of stylus elements is not vital to the invention, nor the specific position relative to the base plate. The invention fundamentally contemplates a resiliently clamped quickly attachable or detachable line drawer adapted to be'placed upon any desired type bar in overlying position with respect to the characters on said type bar and of such depth dimension asto take up the lost motion between the type bar and the resilient tongue integral with said top strap extending downwardly from the rear endthereof parallel to said base plate, and rolling styluses mounted in upper and lower case positions on the front of said base plate.

2.-Line drawing attachment for typewriters adapted to be spring retained on the type end of any type bar of a typewriter comprising means forming a socket member adapted to be slipped endwise on the type bar in the direction of its axis to a definite position, said means including a base plate engageable with the type face of the type bar, a top strap extending rearwardly from the top of said base plate perpendicular thereto for enagagement with the end of the type bar, resilient side wings extending rearwardly from the sides of said base plate, a resilient tongue extending downwardly from the rear end of said top strap and integral therewith, and rolling styluses in upper and lower case positions mounted on the front of said base plate at such distance therefrom to take up the 10st motion betweenthe type bar and platen, normally present when the operating key of the type bar is in depressed position.

BRADLEY L. CLARK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,206,972 Anderson Dec. 5, 1916 1,915,426 Kohler June 2'7, 1933 FOREIGN PATENTS Number Country Date 546,834 Germany 1932 Great Britain 1930 

